Transmission replace

[Junior Lepard]

I have a 2003 chevy tahoe z71 5.3L flex l59.  4x4 And my transmission is a m30. 3kcd it says that that's the only tranny that works is 03 I have an option to get a  2004 Chevy Suburban with the 5.3L flex I-59 AWD and the m30 tranny but it's a 4kcd why will it not work any ideas everybody's telling me they don't. And some say it will both have the vin z motor. O and i will be using the torque converter that comes with the tranny

[Junior Lepard]

On 3/13/2020 at 7:06 AM, Junior Lepard said:

I have a 2003 chevy tahoe z71 5.3L flex l59.  4x4 And my transmission is a m30. 3kcd it says that that's the only tranny that works is 03 I have an option to get a  2004 Chevy Suburban with the 5.3L flex I-59 AWD and the m30 tranny but it's a 4kcd why will it not work any ideas everybody's telling me they don't. And some say it will both have the vin z motor. O and i will be using the torque converter that comes with the tranny

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